The invention relates to the use of etilefrin and etilefrin pivalate in the treatment of circulation disorders.
The sympathomimetic drug etilefrin has been used heretofore as a rapid acting medicine in circulation disorders, in particular in hypotonia and orthostatic hypotension and is described in standard pharmacological works exclusively as a means to increase blood pressure. The increase in blood pressure is effected by the known vasoconstrictory action of the substance. Etilefrin has in addition to its vasoconstrictory action, also a stimulating effect on the heart, which, however, is manifested only by a very slight increase in the cardiac output. In the case of the oral or parenteral administration of such sympathomimetic agents, in addition to an increase in blood pressure, simultaneously an undesirable acceleration of cardiac frequency is observed, in particular if an attempt is made to obtain a relevant rise of the cardiac output by the administration of higher doses of the active ingredient.
In view of the short half-life of 2.2 hours for the elimination of etilefrin from the blood circulation, no stable, increased blood pressure amplitude can be obtained in the patient even with the administration of higher doses, even though this is a necessary requirement in the long term elimination of circulatory disorders and their symptoms. If the circulation disorders are due to cerebral or peripheral arterial stenosis, such as in the case of arteriosclerosis or to cerebral vasoconstriction as in migraine, the application of etilefrin may even be inappropriate in view of its vasoconstrictory effect, as a further reduction in the lumen of peripheral vessels would necessarily lead to a further deterioration of circulation.